Yes, the garage door closer is indeed a clever circuit design but there are real life reasons why garage door manufacturers do not put an auto-close feature on their products. Liability and safety!

I can see a small child injured, the back of your car or something else being damaged when the door goes down without human intellect. What about being automatically locked out of your own garage! Some newer door systems have a door obstruction safety but a safety control should never be used as an operating control. Why trust that to avoid an injury when you set up an accident scene? A much better project would be a flashing light at the garage exit as a reminder to close the door. The red LED on the control box is garnish rather than function.

Sorry, I am thumbs down on this one and it is featured on the front cover no less!

Len

Len

“To invent, you need a good imagination and a big pile of junk.” (T. Edison)
"I must be on the way to success since I already have the junk". (Me)

My door closer has a photo eye safety that would detect a person or vehicle in the door path, but I still have two issues with it:
1. You must have a number pad entry device in case you forget both your key and setting the override when gardening etc.
2. You should never depend on this for more than a backup. I had my door fail to close because a moth flew in front of the safety photo sensor. I had that happen again when the wind blew a leaf in its path. Since then, I always pause in my drive to verify my door closed fully, but I have forgotten to close it after gardening.

This article gave me ideas for two additional projects:
1. A button to trigger the light timer so I will have light to get into the car before opening the door to the cold wind.
2. I'd also like to tap that photo sensor to ring my doorbell but only after the light on the opener times out. I sometimes leave the garage door open for visitors, but linking it to the light would prevent the bell from ringing from normal entry or exits. This also provides some protection if the override is forgotten - like when I work in the garden.

I built the garage door closer. My wife keeps forgetting to close the door when she comes home. No more leaving for work and finding the door has been open all night! Because the circuit works in parallel with the normal close button it does not defeat the normal safety features - if something blocks the electric-eye or offers more than a few pounds of resistance the door will reverse and go back.

I know this is a really late post, but I worked with someone's garage door opener for a while. The unit has a safety device that prevents the door from closing if someone moves into the path of the door. In fact I had to replace the safety device itself because it would not allow the door to close; it turned out to be defective. I installed and tested a replacement unit it and it worked fine. While it is good to keep safety in mind at all times, I think a much greater hazard to children comes from drivers who reverse an SUV vehicle but they either cannot see a small child in the path of the SUV or the SUV is an older model without a backup camera installed and they can't recheck the rear of the vehicle to make sure the path is clear. Fortunately it looks like backup cameras are pretty standard on new vehicles of very size now.

It is too bad that commercial garage door opening devices are not open sourced because you can do some interesting things by modifying the code that opens and closes the door.

[quote="BobCochran13"][size=150][color=#0000FF]I know this is a really late post, but I worked with someone's garage door opener for a while. The unit has a safety device that prevents the door from closing if someone moves into the path of the door. In fact I had to replace the safety device itself because it would not allow the door to close; it turned out to be defective. I installed and tested a replacement unit it and it worked fine. While it is good to keep safety in mind at all times, I think a much greater hazard to children comes from drivers who reverse an SUV vehicle but they either cannot see a small child in the path of the SUV or the SUV is an older model without a backup camera installed and they can't recheck the rear of the vehicle to make sure the path is clear. Fortunately it looks like backup cameras are pretty standard on new vehicles of very size now.

It is too bad that commercial garage door opening devices are not open sourced because you can do some interesting things by modifying the code that opens and closes the door.

Bob
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Most of the openers I've seen have the "safety device" placed about 8" above the floor. I had to repair one a while back where the owner didn't pull far enough in.The rear tires on his truck were in the garage, not blocking photo eye, but his ClasIII trailer hitch was still in the path of the door. The door had no other auto reverse other than the photo eye. When the owner tried to pull in further, that's when he found out the door had come down between the truck and the ball on the hitch. The bottom panel was bent badly and had to be replaced. Owner wanted me to raise the photo eye, I refused and added a second one to catch obstructions both high and low.

I think you make a great point. Some sort of downward looking sensor mounted on the...garage door?...garage ceiling?...is needed that can spot obstructions like those you describe. A range finder could do it: if the door opener code can be set with the exact distance from some overhead point x to the floor of the garage y, and then repeatedly take this measurement again during the door closing operation, it could be determined that an obstruction is in the way of the door. Something of this sort, but downward looking and perhaps even a third set of sensors that are upward looking could be employed.

On that note, the robotic component pickers and placers aren't only for production speed anymore. It's just not humanly possible for their assemblers to place them. Oh, for the good old days of thru hole!!